This invention relates to a submersible power unit and more particularly to an improved small propulsion unit that can be employed by swimmers or for snorkeling.
There has been proposed a very small type of compact water propulsion unit that is designed for use primarily for snorkelers or swimmers. This propulsion unit is comprised generally of a frame assembly that mounts an internal combustion engine and a propulsion device which is driven by the engine. With this type of arrangement, the engine is operated at least in a partially submerged condition and the induction system for the engine includes an air box that draws air through an air inlet device that extends above the water level. This type of unit has relatively low power but can be employed for the purposes as aforenoted.
Obviously, this type of unit is designed to be operated only at relatively shallow depths and hence the air inlet device only extends a small distance above the water level. However, there are many instances when the unit may be submerged to a level greater than the air inlet device can operate and this can cause the ingestion of water.
It is, therefore, a principal object of this invention to provide an improved air inlet device for a submersible power unit.
It is a further object of this invention to provide an improved air inlet device for a submersible power unit that will ensure against the ingestion of water if the unit is submerged to a level greater than it is designed for.
In order to permit the engine to operate in a submerged or partially submerged state, it is necessary that a number of the auxiliaries for the engine be protected from the water. However, these components also are such that should be easily accessible. Therefore, the components are generally provided within a watertight environment with one or more access plates that can be removed to permit servicing of the components. Examples of such components are the battery, spark plugs, and other like components of the engine that require frequent servicing.
However, the aforenoted types of constructions and particularly those employing closure plates that are held on by screws give rise to substantial sealing problems.
It is, therefore, a still further object of this invention to provide an improved submersible power unit wherein certain components to be serviced are contained within an air chamber and can be easily accessed through a large closure that is well sealed to the air chamber.